<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<form>
			用户名：<input type="text" autofocus required name="username" placeholder="请输入用户名">
			密码：<input type="text" autofocus required name="password" pattern="\w{6,19}" placeholder="请输入密码" title="请输入6到19位的密码">
			<input type="submit" value="提交">
		</form>
	</body>
</html>